Top Transport Canada officials — and possibly Minister Lisa Raitt — could be on the hot seat next week as MPs hold emergency hearings on railway safety.

Olivia Chow, NDP transport critic and vice-chair of the House of Commons transport committee, requested the meeting and garnered the required support from three fellow MPs on the panel. She wants the deputy minister or designate to explain why key recommendations from the Auditor General of Canada and the Transportation Safety Board have not been implemented — and if there's a timeline in place to proceed.

"What’s the plan? Why aren't these happening? Is there any documentation as to the reasons? Tell us. Be accountable," she said.

Meeting scheduled for Tuesday

The chair is required to convene the meeting within five days, and the meeting has now been scheduled for 4 p.m. Tuesday. But it's not clear if the Conservative majority on the committee will actually allow witnesses to testify, or if it will be a closed-door planning session. Chow said she would also like to hear from new Transport Minister Lisa Raitt, because hearing about her "work plan" would offer Canadians some assurance.

While the process is not meant to lay blame, Chow said there are critical questions of accountability around why recommendations were never acted on — including the two made by the Transportation Safety Board today on unattended trains and the carriage of dangerous goods.

"This is not the first time they said that regulations regarding the braking system needs to be clearer, needs to be stronger. Had Transport Canada not ignored the Transportation Safety Board’s recommendations a few years ago — and there were several examples — perhaps things would have been different. Because they spelled it out. "

Asked if she was suggesting the train tragedy could have been prevented if those recommendations had been adopted, Chow said it is premature and counter-productive to point fingers right now.

'Not the time for politics'

In an interview with CBC News, chairman of the House of Commons transport committee, Conservative MP Larry Miller, called the hearings "premature" but confirmed he will convene a meeting by the deadline. He said it will be up to the committee to determine how the process unfolds.

"This is not the time for politics and if there's something we can accomplish, by all means we'll do what we have to," he said.

Miller also said MPs would consider recommendations from the Transportation Safety Board, but would not prejudge anything at this time.

Disaster workers found the remains of four more victims on Thursday in the red zone of the town where the train carrying crude oil derailed and set off a series of explosions. Quebec provincial police confirmed the official death toll is now 42, with eight more people unaccounted for and presumed dead.

The unmanned train — all but one of its 73 cars carrying crude oil — hurtled down a 11-kilometre incline, derailed and exploded in the centre of town. The deadly crash has touched off a political debate about train safety in Canada.

Transportation Safety Board 'making good progress'

Transportation Safety Board officials delivered an update on the investigation this morning, and said officials are "making good progress." The TSB is asking Transport Canada to review operating rules around securing unattended trains and trains carring dangerous goods.

Officials said the investigation remains the board's "top priority" across all modes of transport. Investigators on site and in Ottawa are reviewing voice recorder data, inspecting tracks and cars and taking photographs and measurements to help calculations to understand what happened.